Decomposition of organic hydroperoxides



Patented June 26, 1951 I nacourosmos or ORGANIC maorsaoxmns George E.Boise and Edwin J. Vandenberg, Wilmington, Del.I assignors to HerculesPowder Company, Wilmington, Del., a corporation of Delaware No Drawing.Application November 24, 1948. Serial No. 61,931

11 Claims. (01. 260-392) This invention relates to a process for theproduction of alcohols and ketones from tertiary organic hydroperoxides.More particularly, the invention relates to a process for the productionof aromatic ketones and tertiary alcohols containing an aromatic nucleusby the reaction of a,s-dialkylarylmethyl hydroperoxides with the reducedform of certain electromotive couples.

It has been known that certain organic hydroperoxides would undergothermal decomposition to produce various reaction products. However,since the ,-dialkylarylmethyl hydroperoxides of this invention arerelatively stable thermally, it has been desirable to discover aprocedure different from thermal decomposition whereby thehydroperoxides could be decomposed to useful reaction products.

I In accordance with this invention, it has been discovered thattertiary alcohols containing an 1 aromatic nucleus and aromatic ketonesmay be produced by the reaction between an ,-dialkylarylmethylhydroperoxide having the structural formula in which R1 and R: representalwl groups and Ar represents a substituent selected from the groupconsisting of aryl and alkaryl groups, and the reduced form of anelectromotive couple having a standard oxidation-reduction potential notless than about -'-l.0 volt.

The tertiary alcohols which may be produced by the process of thisinvention may be represented by the structural formula 2 produced may berepresented by the structural formula I the intermediate range of fromabout 0.3 volt to about -0.2 volt.

process of this invention. When the two alkyl groups represented by thesymbols R1 and R: of the structural formula for thea,a-dialkylarylmethyl hydroperoxides are the same. only one aromaticketone can, of course, result from the decomposition of thehydroperoxide molecule. Thus, in the case of ,a-dimethylbenzylhydroperoxide, only acetophenone can be formed.

The standard oxidation-reduction potentials to which reference is madeherein are the values in volts of the electrical potential of the couplein question determined at 25 C. under a pressure of one atmosphere withsolutions of one molal activity referred to the potential of thehydrogenhydrogen ion couple as zero. The sign of the oxidation-reductionpotential values is positive, if the reduced form of the couple is abetter reducing agent than hydrogen; negative, if the reduced form ofthe couple is a weaker reducing agent than hydrogen.

During the process of this invention there is formed in the reactionmixture an electroinotive aaaaoes couple, the reduced form of which isone of the initial reactants. The reduced form may be designated ametallic reducing agent, and the term metallic reducing agen is utilizedherein to designate all of those materials which contain metallic atomsand which are capable of acting as reducing agents, i. e., which arecapable of donating an electron to other components of the reactionmixture. Thus, there is embraced by the term metallic reducing agent"not only the free metallic ions such as the ferrous ion (Fe++) but alsocomplexes of such metallic ions such as the ferrous pyrophosphatecomplex. Likewise included are metals such as silver and metalliccompounds which are substantially completely insoluble but whichnevertheless act as reducing agents such as, for example, ferroushydroxide (Fe(OH) 2) which forms'the couple the standardoxidation-reduction potential of which is +0.56 volt.

The a,a-dialkylarylmethyl hydroperoxides which are operable in theprocess of this invention are tertiary organic hydroperoxides and may beprepared by the oxidation of alkyl-substituted aromatic organiccompounds having the following structural formula matic organiccompounds which may be oxidized to produce the hydroperoxides, but alsoto the hydroperoxides themselves and to the ketones and alcohols whichmay be produced by the process of this invention, the aryl andalkaryl'groups need not be derived from benzene as is the case p in thespecific hydroperoxides and aromatic hydrocarbons previously listed, forcompounds containing aromatic nuclei derived from naphthalene,anthracene, phenanthrene, and the like are also operable. For thealkaryl groups the aryl portion thereof may be substituted with alkylgroups such as methyl, ethyl, propyl, isopropyl, butyl, isobutyl,secondary butyl, tertiary butyl, and the like to give alkarylsubstituents. In the structural formulae for the hydroperoxides, thehydrocarbons from which they are derived and the alcohols formed, R1 andR2 may be either the same or different and may be represented by thesame alkyl groups as those listed above as aryl substi'tuents.

Although all of the organic hydroperoxides,

peroxide, a,-dimethylp=-isopropylbenzyl hydroperoxide,a,a,a.',a.'-tetramethyl-p-xylylene dihydroperoxide,a-ethyl-a-methylbenzyl hydroperoxide and a,c-dimethylnaphthylmethylhydroperoxide are preferred. Particularly preferred is 11,11-dimethylbenzyl hydroperoxide. From a,u.,a.',a'- tetramethyl-p-xylylenedihydroperoxide and from similar dihydroperoxides, tertiary aromaticdialcohols and diketones such as' a,a,a',a'-tetramethyl-p-xylylenedialcohol and p-acetylacetophenone may be prepared. Likewise, mixed ketoalcohols such as p-acetyl-a,a-dimethylbenzyl alcohol may be produced. Inaddition, from the dihydroperoxides there may be prepared analogousmixed keto hydroperoxides such as p-acetyla,-dimethylbenzylhydroperoxide and mixed hydroperoxy alcohols such asa,a,a.',a'-tetl'amethyl-p-xylylene monoalcohol monohydroperoxide. Thedihydroperoxides are the c,a,a',o.'- tetraalkylaryldimethyldihydroperoxides which are the further oxidation products of those(1,1:- dialkylarylmethyl hydroperoxides containing an additional alkylsubstituent having a tertiary carbon atom attached directly to a carbonatom of the aromatic nucleus. y

In the practice of this invention, several modifications of thehydroperoxide material may be utilized. The hydroperoxide may be used,for example, either in the form of the pure hydroperoxide, or in theform of a crude reaction mixture containing the hydroperoxide andobtained by the oxidation with molecular oxygen of an alkyl-substitutedaromatic organic com-, pound having the structural formula shownpreviously. When the hydroperoxide is obtained by such an oxidation, theoxidation'usually is interrupted before all of the hydrocarbon hasreacted in order to avoid or limit side reactions. In this manner, thea,e-dialkylarylmethyl hydropero'xide usually is obtained in mixture withsmaller or larger amounts of the original hydrocarbon, which is ana,a-dialkylarylmethane, and the mixture also may contain secondaryreaction products such as the corresponding alcohols, which area,a-dialkylarylmethyl alcohols. The oxidation of cumene. for example,may lead to a reaction product containing a,a-dimethylbenzylhydroperoxide, a,a-dimethylbenzyl alcohol, a smail amount ofacetophenone, and unchanged cumene. Such a reaction product may be usedper se in the process of the invention. In case it is desirable,however, to obtain the hydroperoxide in a more concentrated form, thehydroperoxlde may be separated from the other constituents of the crudereaction mixture. The hydroperoxides may be separated from the reactionmixtures by, for example, fractional distillation at very low pressures,or the order of 0.01 to 1.0 mm. of mercury, the hydroperoxides havinghigher boiling points than the related hydrocarbon, alcohol, and ketone.a,a-Dimethylbenzyl hydroperoxide, for example, distills at 60 C.-

under a pressure of 0.2 mm. and at 68 C. under a pressure of 0.3 mm.droperoxides also may be separated from the oxidation reaction mixturesby crystallization, which may be facilitated by first distilling off atleast part of the hydrocarbon. Steam distillation usually is suilicientto remove the hydrocarbon. Another method of separating thehydroperoxides from the reaction products involves precipitation of thehydroperoxide with a concentrated aqueous solution (25% to 40%) ofsodium hydroxide. The precipitate is crystalline.

In some instances, the hy- 5 The precipitate of .a-dimethylbenzylhydroperoxide, for example, analyzes for the sodium salt 01' thehydroperoxide associated with tour mole cules of water.

Having thus described the general nature of this invention, thefollowing examples are 01'- i'ered to illustrate the practice thereof.All parts are by weight unless otherwise indicated.

EXAMPLE 1 with all of the cobaltous ions present, was added slowly andwith agitation over a period of about one hour. Bythis means, cobaltoushydroxide was formed and the a,c-dlmethylbenzyl hydropcroxide wasdecomposed.

The progress of the hydroperoxide decomposition reaction was followed bytreating aliquot portion of the reaction mixture, after filtering oilthe cobaltous hydroxide, with acidified potassium iodide and noting theamount of iodine liberated by the unreacted hydroperoxide. The entireexperiment was carried out under an inert atmosphere to prevent theair-oxidation of the metallic reducing agent. Upon completion of theaddition of the sodium hydroxide, analysis of the reaction mixtureindicated that 82% of the madimethylbenzyl hydroperoxide had beenconverted to iaa-dimethylbenzyl alcohol and that about 8.5% of thehydroperoxide had been converted to acetophenone. The above exampledemonstrates Table 1 l R Pg 2 :13:1 P C t I Mo es of e- 1' er en 0 ducing f fig Hydro r- Original Reducing Agent and Tempera- Reaction H Agent Aded H i oxide onlgdro r- Source ture Time p per Hydrooxgde verted to a,0 do onroxide 00m Bed a-Dimetliylverted to olecule benzyl AcetophenoneAlcohol 5. 7 4.0 2. l 4. O 2. 02 4. 4 2. 5O 2. l 2. 5O 4. 0 2. 02 4. 42. 50 l 11 11 Do.--" lhl.---. 2.1 2.50 '83 l9 Fe++(FeS04.7H;0) 20 C.Instant 4. 0 1.44 1 100 5 87 D0 5;l 2 C 5Min 4.0 1.44 100 5 87CUCKCIJCI) 20 C-- Instant 2.1 2.02 3 100' 0 100 Sn (SnCh.2HzO) 21 0...d0. 2 2. 2 1 100 100 0* K '(CrCh) 20 C d0... 4 2. 2 2 100 0 la,a-Dimethylbenzyl hydroiseroxide hydroperoxide, 17% u,-d1.methy 1a,a-Dimethylbenzyl hydroperoxide prepared repared b the air-oxidation oicumene and containing 70% of the benzyl a cohol, 5.6Zfscetophenonc, and7.4%

unreacted cumene.

y the air-oxidation of cumene and containing 46% of the hydroperoxide,3.2% acetophenone, 2% c,a-dimethylbenzyl alcohol, and-48 .8% unreactedcumene.

The data recorded in the above table clearly demonstrate the remarkableadvantages which attend process of this invention; By virtue of thisprocess, a,-dialkylarylmethyl hydroperoxides may be converted in nearquantitative yield either to the corresponding tertiary alcohols oraromatic ketones at temperatures far below the EXAMPLEZ To 400 parts ofwater was added, with agitation, 59.5 parts of cobaltous chloridehexahydrate (0061161120) and 23.6 parts of -a,c-dim'ethylbenzylhydroperoxide. After the cobaltous chloride had dissolved and thehydroperoxide had become evenly dispersed throughout the aqueous medium,a quantity of 4 N aqueous sodium hydroxide, in excess or that requiredto react that the process of this invention is operable in alkalinemedium to produce alcohols and ketones from a,a-dialkylarylmethylhydroperoxides at room temperature in excellent yield.

This example also illustrates that metallic reducing agents, inoperableunder a particular set of conditions, may be rendered operable byaltering the reaction conditions. Thus, cobaltous ions, which in acidicmedium are inoperable because of the low standard oxidation-reductionpotential of the couple formed (-1.84 volts) are operable in alkalinemedium to produce tertiary alcohols by the process of this invention.Under the conditions employed in this example, cobaltous hydroxide formsthe couple which has a standard oxidation-reduction potential of about0.2 volt. The a,a-dimethylbenzyl hydroperoxide employed in this examplewas prepared by the air oxidation of cumene and contained 01 thehydroperoxide, 17% of G,G-d1- methylbenzyl alcohol, 5.6% acetophenoneand 7.4% unreacted cumene.

EXAMPLEEI u,-Dimethylbenzyl hydroperoxide was converted to,a-dimethy1benzy1 alcohol in a manner similar to that described inExample 2. In this case, however, manganous sulfate monohydrate(MnSO4.H:O) was employed as a reactant. The a,c-dimethylbenzylhydroperoxide utilized was of the same composition as that described inEx- ,-dimethylbenzy1 hydroperoxide had been consolubility (Kaol.-'- 4X10 of the manganous hydroxide, as a consequence of which, the number ofelectrons available for reaction at any particu lar instant was sharplyreduced.

EXAMPLE 4 v To 38 parts of water was added 0.42 part of sodiumpyrophosphate decahydrate When the sodium pyrophosphate was completelydissolved, 0.0175 part of a reaction product containing 46%a,a-dimethylbenzyl hydroperoxide suspended in seven parts of water wasadded with agitation. The e,-dimethyl- I benzyl hydroperoxide wasfollowed by the addition of 0.047 part of ferrous sulfate heptahydrate(FeSO4.7H2O) dissolved in five parts of water. The pH of the resultantreaction mixture was 10.2. One day after the addition of the ferroussulfate had been completed, analysis indicated that 91% of thea,a-dimethylbenzyl hydroperoxide had been decomposed and that 72% of thetheoretical amount of acetophenone had been formed.

This example indicates that metallic reducing agents, which in theirnormal state, would be inoperable to produce a particular alcohol orketone maybe altered by complexing the same with certain organic orinorganic complexing reagents in such a manner that the desiredoxidationreduction potential is obtained. Thus, ferrous hydroxide, whichwould normally be produced at a pH of 10.2, forms a couple, the standardoxidation-reduction potential of which is +0.56

' volt, and would react with a,a-dimethylbenzyl hydroperoxide to producea,a-dimethylbenzyl alcohol.- Hcwever, by complexing the ferrous ionspresent with pyrophosphate ions, it is possible, as indicated by thisexample, to produce a metallic reducing agent, the standardoxidationreduction potential of which is within the range of from about-1.0 volt to about 0.3 volt and 1 acetophenone and 48.8% unreactedcumene.

. v EXAMPLE 5 a,-Dimethylbenzy1 hydroperoxide in dilute aqueous solutionwas admixed at a pH of 3.2, 2.7, v and 1.8 with aqueous ferrous sulfatein such a manner that there was present for each hydro- V peroxidemolecule 0.28 ferrous ion. Analyses of phenone.

portions of the reaction mixture were made after approximately threehours and after three and seven days following the addition of theferrous sulfate. The results of these analyses appear in Table 2.

A similar dilute aqueous suspension of ,-di-

methylbenzyl hydroperoxide was admixed with aqueous ferrous sulfate at a,pH of 3.0 in such a manner that there was present 14.4 ferrous ions perhydroperoxide molecule. Approximately three hours after the addition ofthe ferrous sulfate, 89% of the a,a-dimethylbenzyl hydroperoxide hadbeen converted to acetophenone as indicated in Table 2.

Table 2 it t 1' core on ggfl fisg Per Cent of Amount of per Hy at pHReaction Original Hy- Acetophenone peroxide Time droperoxide FormedBased Molecule Decomposed on Amount of Hydroperoxide Decomposed 0. 28 3.2 2-3 hours. 17 18 0. 28 3. 2 3 days 17 i8 0. 28 3. 2 7 days 20 25 0. 282.7 2-3 hour-5-... 23 18 0. 28 2. 7 3 days 26 23 0. 28 2. 7 7 days 31 250.28 1.8 2-3h0urs-.-. 20 18 0. 28 l. 8 3 days 24 23 0. 23 l. 8 7 days 3729 0 l. 4 2-3 hours. 5 0 (l i. 4 3 days 20 4 0 i. 4 7 days 34 9 1.65 3.2 Instant I 87 14.4 3.0 .do 100 89 l Ldli ferrous ions consumed perhydroperoxide molecule decompose It is apparent from an examination ofthe above table that action of the metallic reducing agent is not merelycatalytic in effect. It is further apparent that there is required foreach hydroperoxide molecule decomposed, approximately that amount ofreducing agent which is capable of donating one electron. Likewise, itis evident that no particular advantages such as increased yield orreaction rate are resultant from the utilization of a quantity ofreducing agent appreciably in excess of that required to provide oneelectron per hydroperoxide molecule.

EXAMPLE 6 A suspension of 32.4 parts of ferrous chloride tetrahydrate(FeClzAHzO) in 178 parts of glacial. acetic acid was prepared. To thissuspension was added dropwise with agitation over a period of about 50minutes, 100 additional parts of glacial acetic acid in which wasdissolved 18.5 parts of a.a-dimethylbenzyl hydroperoxide. The reactionwas carried out in a closed system at a temperature of 20-25 C. By thismeans 83% of the original ,-dimethylbenzyl hydroperoxide was convertedto aceto- This example shows that the process of this invention may becarried out in organic solvents.

EXAMPLE 7 Three hundred and sixty-five parts of a, water solution ofa,a-dimethyl-p-methylbenzyl hydroperoxide containing 0.398 part of thehydroperoxide, and 515 parts of water were placed in a closed vesselafter nitrogen had been swept through the total water solution to removeany air present. In the absence of air there then was added to thevessel 12 parts of 0.0413 N ferrous sulphate solution. The reaction wascoma a plate in less than nve minutes. about 1.8 Ib++ per hydroperoxidemolecule having been consumed. Analysis of the reaction mixtureindicated that a 07% yield of p-methylacetophenone was ob- EXAMPLE 8 Onehundred parts of a,,a',a'-tetramethyl-p- 'xylylene dihydroperoxide and6000 parts of water from-which air had been removed bvsweeplng withnitrogen were placed in a closed reaction vessel. To the vessel then wasadded 2000 parts of an aqueous solution of ferrous sulfate containing402 parts of FeEiOdIHzO. The temperature was about 20 C., and the amountof ferrous sulfate represented 1.93 Fe++ per hydroperoxy group.Immediate reaction occurred, as evidenced by color change. and thevessel was maintained at a constant temperature of 25 C. for 1.3 hours,after which analysis showed that 1.18 Fe++ per hydroform couples havinga standard oxidation-reduc- 10' agents which form couples of standardoxidation-reduction potential of less than about -l.0 volt do not react.

It is known in the art that various metallic reducing agents may becomplexed or otherwise modified with various organic or inorganicradicals to produce couples characterized by standardoxidation-reduction potentials quite at varlance to those of theuncomplexed material. By this means, reducing agents which, in theirnorpemxy group had been consumed After an addi mal state, are inoperableto produce a particular tional 16 hours at C. the ferrous ion contentwas the same as after 1.3 hours, consequently the reaction wasterminated.

The insoluble material present, which was composed of organic materialand ferric hydrox- 2 ide, was filtered oil, the precipitate extractedwith ethyl ether, the ether removed from the extract, and the extractedorganic material dried to constant weight to give 15.9 parts of a solidproduct. A, portion of the latter was purified by recrystallization,once from petroleum ether and once from a mixture of petroleum ether andethyl ether..,. The purified product was composed of white, soft, flakyodorless crystals, and was identifled by melting point (112.5113.5 C.)and carboa-hydrogen analysis as p-acetylacetophenone. Further evaluationof the original product showed the presence ofp-acetyl-a,a-dimethylbenzyl alco-' he], and analysis indicated thatapproximately of the total ketone groups theoretically ca- 4 pable ofbeing formed, based on the dihydroperoxide, actually had been formed.

As previously indicated, the nature of the prodalcohol or ketone as aconsequence of forming a couple of improper standard oxidation-reductionpotential, may be utilized. Likewise, variations of the pH at which thereaction'is carried out, and the solubility of the various metallicreducing agents employed may eflect the nature of the couples formed. Aspreviously mentioned, the term metallic reducing agent is employedherein to designate all those reducing agents in 0 which metallic atomsare present. Table 3 constitutes a list of some of the operable reducingagents which may be employed and the products thereby obtainable inaccordance with this invention. For the data of Table 3 and data on 3additional operable couples, reference is made to Lange, Handbook ofChemistry, 6th ed., pages 1073 and 1074, and to Latimer and Hildebrand,Reference Book of Inorganic Chemistry, revised ed. (1940), Appendix 2,pages 474-481, for a tabulation of the electromotive couples formed bythe metallic reducing agents under various reaction conditions and ofthe standard oxidation-reduction potentials of these couples.

.ucts which may be produced in accordance with the process of thisinvention is dependent upon the relative strength of the electromotivecouples which may be utilized. Those reducing agents,

The process of this invention is preferably practiced by the gradualaddition with agitation of an aqueous solution or suspension of themetallic reducing agent employed to an aqueous which under the reactionconditions, form a suspension of an a,a-dialkylarylmethyl hydrocoupl:which is characterized by a standard oxidation-reduction potential offrom about 1.0 volt to about 0.3 volt react with thea,a-dialkylarylmethyl hydroperoxides to produce aromatic peroxide.However, the entire quantity of the metallic reducing agent may be addedat one time. Likewise, the aqueous suspension of a,a-dl81ky1- arylmethylhydroperoxide may be added to the soketones. Likewise, those reducingagents which lution of the metallic reducing agent or the two re- 11actants may be simultaneously charged into the reaction vessel. Ifdesired, an aqueous solution or suspension of the reducing agent may beadmixed with a substantially anhydrous hydroperoxide. Likewise, ananhydrous, liquid, ororganic medium of polar nature in which ionizationis possible may be utilized. Glacial acetic acid is exemplary of such amedium. The quantity of aqueous or liquid polar organic medium utilizedmay be varied widely, but it is necessary that therebe suflicientaqueous or polar organic medium present to permit ionization to occur.Whatever the order or method of addition of the reactants, it isdesirable that the reaction mixture be thoroughly agitated and that thereaction be eflected in an inert atmosphere to prevent air oxidation ofthe metallic reducing It is preferred that the metallic reducing agentbe employed in such amount that there is added in the reaction mixture asuilicient quantity thereof to provide one electron for each hydroperoxyradical it is desired to reduce. .Nlear quantitative I I yields of thetertiary alcohols or aromatic ketones Greater concentrations of metallicreducing agent may be utilized, if desired, but no particular advantagessuch as increased yield or greater reaction rate are thereby attained.The utilization of such an amount of metallic reducing agent that thereis added to the reaction mixture less than that amount required toprovide one electron for each hydroperoxy radical results in acorrespondingly lower yield of the desired product. These resultsindicate that the organic hydroperoxide decomposition reaction of thisinven tion is one of electron transfer. Thus, there must be provided oneelectron for each hydroperoxy radical it is desired to reduce. However,some reduction of the metallic reducing agents oxidized in the course ofthis reaction may occur by a reverse electron transfer mechanism,consequently some metallic ions may take part in the decomposition oftwo or more hydroperoxy radicals. In such instances slightly less thanthat amount of reducing agent required to provide one electron perhydroperoxy radical may sometimes be consumed. Particularly is this truewhen the reaction is effected in an inert atmosphere. When the reactionis not carried out in such an inert atmosphere, a slight excess ofreducing agent should be employed to compensate for the loss due to airoxidation.

The process of this invention may be carried out at any temperaturebelow the thermal decomposition point of the a,a-dialkylary1methylhydroperoxide it is desirable to utilize, but for all practical purposesthe temperature may be between about and about 100 C. No particularadvantage attends the use of elevated temperatures and the process isnormally carried out at temperatures of about to C. It is an importantfeature of this invention, however, that the process thereof may bepracticed at quite low temperatures, such as, for example, about 0 C. toabout -70 C., and at such temperatures the process may be carried out inan aqueous medium by the utilization of a water-soluble organic compoundof low freezing point as antifreeze agent. The reaction medium may be,for example, a mixture of water with methanol, ethylene glycol,glycerol, or other aliphatic alcohol, glycol or poly'glycol.

between a,a-dimethylbenzyl hydroperoxide and the ferrous (Fe++) ion asan example, the formation of several of the reaction products known tobe formed may be explained as follows:

CH) CH] cinio-oon Fe++ cim-c-oonrem CH: O CeHt-(E-O- CIHJL-CB: CH;-

CH3 CH1 CHr- 00H CHr -O CQHP O- C3103 CHr CH CHr-CH;

GB? H10 0 CH '03.

many uses as quotation agents, perfume bases,

wetting-out agents, and the like. This invention accordingly constitutesa most important and significant advance in the art.

What we claim and desire to protect by Letters Patent is:

1. The process of producing aromatic ketones and tertiary alcoholscontaining an aromatic nucleus which comprises reacting ana,e-dialkylarylmethyl hydroperoxide with the reduced form of anelectromotive couple having a standard oxidation-reduction potential notless than about -1.0 volt.

2. The process in claim 1 wherein the reduced form of electromotivecouple is in such concentration that there is provided about oneelectron for each hydroperoxy radical present in the hydroperoxide.

3. The process of claim 1 in which the hydroperoxide isc,e-dimethylbenzyl hydroperoxide and in which the alcohol produced ise,a-dimethylbenzyl alcohol and the ketone produced is acetophenone.

4. The process of claim 1 in which the hydroperoxide isa,e-dimethyl-p-methylbenzyl hydroperoxide and in which the alcoholproduced is a,a-dimethyl-p-methylbenzyl alcohol and the ketone producedis p-methylacetophenone.

5. The process of claim 1 in which the hydroperoxide isa,a,a',u'-tetramethyl-p-xylylene dihydroperoxide and in which thealcohol produced is e,a,e',a'-tetramethyl-p-xylylene dialcohol and theketone produced is p-acetylacetophenone.

6. The process which comprises reacting a tertiary organic hydroperoxidehaving the structural formula R1\ /0 OH 6 R2 Ar with the reduced form ofan electromotive couple having a standard oxidation-reduction potentialbetween about 1.0 volt and about 0.3 volt to produce an aromatic ketonehaving the structural formula and Ar has the same significance in bothstructural formulae and represents a substituent selected from the groupconsisting of aryl and alkaryl groups, and R1 and R2 in the structuralformula for the hydroperoxide represent alkyl groups and R in thestructural formula for the aromatic ketone represents that one of thetwo alkyl groups represented by the symbols R1 and R2 in the structuralformula for the hydroperoxide which is bound to the hydroperoxidemolecule by the strongest carbon-carbon bond.

7. The process of claim 6 in which the reduced form of the electromotivecouple is in such concentration that there is provided about one thehydroperoxide.

8. The process of claim 6 in which the hydro-' peroxide isa,a-dimethylbenzyl hydroperoxide and in which the ketone produced isacetophenone.

9. The process of claim 6 in which the hydroperoxide isa,a-dimethyl-p-methylbenzyl hydroperoxide and in which the ketoneproduced is p-methylacetophenone.

10. The process of claim 6 in which the hydroperoxide is a,a.,a',m'tetramethyl p xylylene dlhydroperoxide and in which the ketone producedis p-acetylacetophenone.

11. The process which comprises reacting a,a-dimethylbenzylhydroperoxide in acidic medium with ferrous ions to produceacetophenone.

12. The process which comprises reacting a tertiary organichydroperoxide having the following structural formula RI OOH with thereduced form of an electromotive couple having a standardoxidation-reduction potential not less than about 0.2 volt to produce atertiary alcohol having the structural formula Rz Ar and R1 and Rhave'the same significance in both structural formulae and representalkyl groups, and Ar has the same significance in both structuralformulae and represents a substituent selected from the group consistingof aryl and alkaryl groups.

13. The process of claim 12 in which the reduced form of theelectromotive couple is in such concentration that there is providedabout one electron for each hydroperoxy radical present in thehydroperoxide.

14. The process of claim 12 in which the hydroperoxide is a,-dimethylbenzyl hydroperoxide and in which the alcohol produced isa,a-dimethyl-. benzyl alcohol.

15. The process of claim 12 in which the hydroperoxide isa,a-dimethyl-p-methylbenzyl hydroperoxide and in which the alcoholproduced is a,a-dimethyl-p-methylbenzyl alcohol.

16. The process of claim 12 in which the hydroperoxide is,a-tetramethyl-p-xylylene dihydroperoxide and in which the alcoholproduced is a,a,a',a'-tetramethyl-p-xylylene dialcohol.

17. The process which comprises reacting madimethylbenzyl hydroperoxidein acidic medium with stannous ions to produce a,a-dimethylbenzy1alcohol.

GEORGE E. HULSE. EDWIN J. VQNDENBERG.

REFERENCES CITED The following references are of record in the file ofthis patent:

UNITED STATES PATENTS Number Name Date 1,813,606 Binapfl et al July 7,1931 2,462,103 Johnson Feb. 22, 1949 OTHER REFERENCES Allen: OrganicSyntheses, (Wiley 8: Sons. N. Y.) vol. 20, pages 94-6 (1940).

1. THE PROCESS OF PRODUCING AROMATIC KETONES AND TERTIARY ALCOHOLSCONTAINING AN AROMATIC NUCLEUS WHICH COMPRISES REACTING ANA,A-DIALKYLARYLMETHYL HYDROPEROXIDE WITH THE REDUCED FORM OF ANELECTROMOTIVE COUPLE HAVING A STANDARD OXIDATION-REDUCTION POTENTIAL NOTLESS THAN ABOUT -1.0 VOLT.